Pneumatic shuttle operating mechanism



No 15, 1949 T. HINDLE 2,488,192

PNEUMAT I C SHUTTLE OPERAT ING MECHANI SM Filed Sept. 28, 1948 4Sheets-Sheet 1 INVENTOR FIGS BY )5, A g IAWM ATTORNEYS Nov. 15, 1949 T.HINDLE PNEUMATIC SHUTTLE OPERATING MECHANISM 4 Sheets-Sheet 2 INVENTOR UXMWJW Filed Sept. 28 1948 S E N R o T A Nov. 15, 1949 I T. HINDLE2,488,192

PNEUMATIC SHUTTLE OPERATING MECHANISM Filed Sept. 28, 1948 4Sheets-Sheet 3 F IGB Flag INVENTOR A'E'IPRNEYS Nov. 15, 1949 T. HlNDLE2,488,192

I PNEUMATIC SHUTTLE OPERATING MECHANISM Filed Sept. 28, 1948 v 4Sheets-Sheet 4 HI "so J 3; I |NVENTOR.

ATTORNEYS Patented Nov. 15, 194

PNEUMATIC SHUTTLE OPERATIN MECHANISM Thomas Hindle, Blackburn, EnglandApplication September 28, 1948, Serial No. 51,540 In Great BritainOctober 4, 1947 6 Claims. (Cl. 139-144) This invention relates to loomsfor weaving and in particular to improvements in looms of the type inwhich the shuttle is expelled from its box and projected across theloom, through the shed and into the opposite box, by the direct actionof a blast of compressed air admitted into the outer end of the boxbehind the shuttle.

One object of the invention is to provide an improved cycle or system ofpneumatic picking of the general type above referred to, whereby thepneumatic picking operation is made more reliable, consistent andeconomical, and also generally more convenient, as the supply ofcompressed air is preferably derived from a central source, such as amotor-driven air compressor, common to a number of looms.

Another object is to provide apparatus comprising a novel combination ofvalves which operate in conformity with the requirements of the cycle.

A further object is to provide convenient and simple means whereby theweaver may withdraw a shuttle from a shuttle-box for the purpose ofrenewing the weft package or for any other purpose.

The improved cycle of operations at each end of the loom according tothe invention comprises the following stages in order of sequence:

1. A charging-bottle of suitable and preferably adjustable volumetriccapacity is placed in communication with a supply of compressed airmaintained at a predetermined pressure, whereby the charging-bottle ischarged with a measured volume or charge of air at the said pressure,such measured volume of compressed air being sufficient to efiect onepick or discharge of the shuttle.

2. The said charging-bottle is isolated from the supply in immediateanticipation of the pick.

3. At the appropriate time for the picking impulse to commence,(preferably following immediately after stage 2), the saidcharging-bottle is placed in full bore communication with the outer endof the shuttle-box, whereupon the measured charge of compressed airexpands into the shuttle-box wherein the pressure of air accelerates theshuttle and discharges it from the box. During the picking impulse anyauxiliary outlets, (such as that referred to in stage 4b) by which thecharged air might escape direct to atmosphere instead of via theshuttle-box, are closed.

4a. Shortly after completion of the picking operation as in stage 3, thecharging-bottle is first isolated from the shuttle-box, and then re- 2stored to communication with the compressed air supply, from whichthebottle thereupon draws a fresh charge of compressed air in readinessfor the next picking operation from the same end.

4b. Concurrently, the shuttle-box, after disconnection from thecharging-bottle as in stage 4a, is placed in communication with a cavityor pocket in the valve-box from which air entering the said pocket fromthe shuttle-box may escape to atmosphere only by passing through anadjustable restriction such as a finely adjustable throttle valve. Thusthe incoming shuttle is checked by its compression of the air trapped inthe shuttlebox, such air, less that portion which escapes by leakagebetween the closely fitting shuttle and the shuttle-box walls, beingforced out to atmosphere through the said restriction.

The invention is illustrated in and will be described with reference tothe accompanying drawings, in which:

Figs. 1, 2, 3, 4 and 5 are diagrammatic views illustrating the cycle ofoperations for picking;

Fig. 6 is a vertical section of one form of valve gear for carrying outthe invention;

Fig. 6a is a detail section view at right angles to Fig. 6 of the checkvalve allowing the escape of air from the shuttle-box as the shuttleenters the box;

Fig. 6b is a detail section view of the pilot valve shown in Fig. 6, thevalve being in its ofi position in Fig. 6, and in its pick position inFig. 6b.

Fig. 6c is a detail sectional view of a modified construction of checkvalve;

Fig. 7 is a partial end elevation of a loom with the slay andshuttle-box shown in section on the line 'l-! of Fig. 6, the pilotvalves being mechanically operated;

Fig. 8 is a plan showing further mechanical means for controlling thepilot valves;

Fig. 9 is a timing diagram;

Fig. 10 is a view showing the pilot valve controlled byelectro-mechanical means;

Fig. 11 is a diagram showing the use of compressed air controlled by ahand-operated valve for expelling the shuttle from the box at lowvelocity, and

Fig. 12 is a diagram showing an electro-magnetically actuated valvecontrolled by a pushbutton for effecting the same purpose as Fig. 11.

The cycle of operations according to the invention is illustrateddiagrammatically in Figs. 1 to 5. In these figures A represents a pipeconnectedto a source of compressed air maintained at a suitable constantpressure, I the chargingvalve 2 the pick valve, 3 the spring loadedcheck valve; 4 an adjustable throttle or choke valve for throttling orchoking the air from the check valve to atmosphere, the charging-bottle,6 the shuttle-box and I the shuttle.

In Fig. 1 the charging-valve I is open to the compressed air supply Aand the charging-bottle 5 is maintained in a fully charged condition.The pick valve 2 is in its closed position, thereby isolating thecharging-bottle from the enclosed shuttle-box 6. The check valve 3 isheld in its closed position by its spring.

In Fig. 2 the charging valve I has been closed to isolate thecharging-bottle 5 from the compressed air supply A, in immediateanticipation of the pick.

In Fig. 3 the check valve 3 is forcibly retained in its closed positionby the push rod 3a, while the pick valve 2 is opened to allow themeasuredcharge of compressed air, previously isolated in thecharging-bottle to expand therefrom into the shuttle-box 6. Theexpanding air exerts pressure on the cross sectional area of the shuttle"I in sufficient degree to drive the shuttle out of the box at thedesired velocity.

In Fig. 4 the check valve 3 is released by retraction of the push rod3a, but the check valve is retained on its seat by its spring.Simultaneously, the pick valve 2 is closed to isolate thecharging-bottle from the shuttle-box, after which the charging valve Iis again opened to admit a fresh charge of compressed air into thecharging-bottle. As shown in Fig. 4 the apparatus is ready to receiveand to check the shuttle when it returns in due course from the oppositeside of the loom.

In Fig. 5 the arriving shuttle traps and compresses the atmospheric airin the shuttle-box B. A portion of such trapped air escapes directly toatmosphere by way of the small clearance between the shuttle I and theclosely fitting walls of the box 6, but the major portion is compressedand forced out past the spring loaded check valve 3 and through theadjustable. throttle or choke valve 4.

The combined resistance of the check valve 3 and the choke valve 4checks the incoming shuttle and brings it smoothly to rest in the box,thus completing the cycle of operations.

A practical arrangement of valve gear for implemjenting the abovedescribed cycle of operations as shown in Figs. 6, 6a, 6band 60, whereinthree poppet or mushroom valves are employed in a valve box 8 providedwith the necessary ports and connections. The valve box is bolted to theouter end of the enclosed shuttle-box 6, in the end of which a port 6aprovides for free passage of air between the valve box and theshuttlebox.

"The first of the three valves is the charging valve I, which opens toadmit. compressed air from the flexible supply pipe A into thecharging-bottle 5, and subsequently closes to isolate thecharging-bottle, thereby. suspending further withdrawal ofair from thesupply.

The second valve is the pick valve 2, which opens to admit to theshuttle-box 6, the measured charge of compressed air from thecharging-bottle 5, and'subsequently closes to seal oif thecharging-bottle before the charging valve I again opens to renew thecharge of compressed air in the bottle.

The third 'valve is the check valve 3, which is forcibly retained in itsclosed position during the picking impulse (that is, while thepick-valve 2 is open), but otherwise is free to be raised off its seatby air compressed in the shuttle-box by an incoming shuttle. This airthen enters the cavity or pocket 9 from which it can escape toatmosphere only by passing through the adjustable throttle or chokevalve 4, or equivalent restriction, which, when suitably adjusted,effectively prevents rebound of the shuttle.

" The three poppet valves I, "2 and 3 may be actuated with the describedeffect by mechanical, electro-magnetic or fluid pressure means, or anycombination thereof.

In the form shown in Fig. 6, the charging valve I and pick valve 2 areprovided with springs Ia and 20. respectively, which act to close thesevalves and retain them on their seats. They are opened as required inthe sequence hereinbefore specified, also the check valve 3 is forciblyretained on its seat during the picking impulse, by means of compressedair drawn from the supply pipe A and admitted under control of a pilotvalve It to three relay cylinders, the co-acting pistons I I, I2 and I3of which are adapted to operate the three valves I, 2 and 3 eitherindependently or collectively in any desired sequence.

As shown in Fig. 6, the three relay cylinders are mounted on the valvebox 8, in axial alignment with the valves. The relay piston I I actuatesthe charging valve I, the relay piston I2 actuates the pick valve 2, andthe relay piston I3 acts to hold the check valve 3 forcibly on its seat.

The pilot valve I0 may be of any suitable type such as a piston or slidevalve or a combination of seated valves. The preferred form is shown inFigs. 6 and 6b and consists of a piston valve of the central admissiontype with widely spaced ports. The pilot valve Ill may be retained inits off position shown in Fig. 6, in which the pick does not occur, by aspring, assisted more or less by gravity or by air pressure, and may beactuated in any convenient manner for the purpose of moving it into itspick" position shown by Fig. 6b.

The pilot valve body Illa is connected to the valve box 8 by pipe I4,which conveys compressed air from the supply pipe A for distribution bythe pilot valve Ill, and by pipes I5 and I6 connected to the relaycylinders containing the relay pistons II, I2 and I3, the pipe I5connecting it to the cylinder containing the relay piston II and thepipe I6 connecting it to the two cylinders containing the relay pistonsI 2 and I3.

When the pilot valve I0 is moved into its ofi position (Fig. 6) airpressure is related from the relay pistons I2 and I3, and consequentlythe pick valve 2 closes under the pressure of its spring 2a, while thecheck valve 3 is left free to open in response to an appreciableincrease of air pressure on its underside, such as that caused by anincoming shuttle. The check valvev is preferably fitted with a lightspring 31), acting to close it and to retain it on its seat. In the offposition, the pilot valve also admits compressed air from the supplypipe A to the relay piston II, in consequence of which the chargingvalve I opens and remains open as long as the pilot valve remains in itsoff position.

When the pilot Valve is actuated so as to move it intoits pick position,shown in Fig. 6b (with the object of initiating a picking impulse at thecorresponding end of the loom) air pressure is first released from therelay piston I I whereupon the charging valve closes under influence ofits spring. and air pressure acting directly on the "valve. As the pilotvalve completes its movement, air pressure from the supply is admittedsimultaneously to the relay pistons i2 and I3, with the result that thecheck valve 3 is forcibly retained on its seat, and then the pick valve2 is forced open, so opening up very smartly full-bore communicationfrom the charging-bottle 5 to the shuttle-box E5, in which latter thecompressed air acts upon the shuttle l in known manner.

Shortly after completion of the pick, the pilot valve ID is caused toreturn to its off position shown in Fig. 6. In the course of thismovement, air pressure is first released from the relay pistons l2 andH3, as the port connecting the pipe 16 to the bore of the pilot valvecasing 18a is opened to the bore above the piston valve, the top of thebore being open to atmosphere, before the port connecting the pipe l5 tothe aforesaid bore is in communication with the port connecting the pipe14 to the bore. Thus, the pick valve 2 closes by reason of its springbefore compressed air is admitted to relay piston l l to re-open thecharging valve l for the purpose of recharging the charging bottle 5, inpreparation for the next picking operation at that end of the loom. Therelay pistons II and [2, after opening their respective valves abutagainst resili nt washers provided in the bottom ends of the relaycylinders.

In a modification of the valve arrangements so far described, theadjustable choke valve 4 is omitted, in which case the check valve 3 isprovided with ready means of adjusting its spring pressure, as shown inFig. 6c in which the spring 3b is adjusted by screwed sleeve 30 providedwith lock nuts 3d. The check valve thus adjustably spring loaded, actsas a throttling restriction for the air compressed by an incomingshuttle and escaping to atmosphere by orifice 3x.

The pneumatic picking apparatus as shown in Fig. 6 is duplicated at theopposite end of the loom slay L, which is supported in the usual manneron slay swords S and is provided with a shuttle race plate T inalignment with the floors of the shuttle boxes 6.

Alternatively, the valve box 8 may be bolted to or made integral withthe front or rear walls of the shuttle box 5, thereby reducing theoverall width of the loom.

The two pilot valves may be actuated by cams revolving at halfcrankshaft speed. Such arrangement is shown by Fig. '7, in which thepilot valve body Illa is mounted underneath the slay. The pilot valve 5at each end of the loom is actuated by a cam l8 secured to a shaft l9revolving at half crankshaft speed. The cam depresses the rear arm ofthe lever 20, which is pivoted at 2| on the loom frame F, and causes thefront arm of the lever 21! to raise the pilot valve, by means of avertical link 23, to its pick position. The spring 2 acts to assist thegravitational return of the lever and the pilot valve to the offposition. The bottom end of link 23 is preferably arranged to coincideas closely as possible with the slay sword rocker shaft 22.

The cam at the other end of the loom is displaced by 180 degrees fromthe position of the cam l8 shown.

Alternatively, the pilot valves may be actuated from a shaft revolvingat crankshaft speed as shown in plan view by Fig. 8, wherein cams I 8are adapted to slide longitudinally along the shaft l9, which isprovided with feather keys or splines to drive the said cams. Twinlevers 25 are pivoted on the loom framework and their free endsconnected together by a link '26, which may be ac-- tuated by a cam orby a dobby or box motioncontrolled by a pattern chain in a manner well:known. The said twin levers engage the cams l8 and slide them endways,so that when one cam actuates its lever 28 and the pilot valve at thatend, the other cam is inoperative.

The pilot valves may also be actuated by elec tromagnetic means as shownby Fig. 10 in which the pilot valves [0 are alternately lifted intotheir pick positions as their actuating solenoids 28 and 28a arealternately energised by the timing switches 29 and 29a. These switchesare selfopening, but are closed momentarily and in correct sequence bythe cam l8 secured to the shaft 1 9 revolving at half crankshaft speed.The energising current for this purpose is drawn from a battery 3!, orother convenient source of electric power, and the circuit includes ahand-operated master switch 39, by which the picking gear may be put outof action while the loom is being turned over for pick finding purposes.

The timing and the power of the picking impulse provided by the hereindescribed apparatus may be readily and independently adjusted to suitall normal requirements.

Fig. 9 is a timing diagram for a wide loom.

'The beat-up position is indicated at O, at which time the chargingbottle is fully charged. At I the pilot valve at one end is moved intoits pick position, and the picking impulse occurs at II-III. The camreturns the pilot valve to its "off position at about IV. The shuttle,after crossing the loom, arrives at the opposite box at V and is checkedand brought smoothly to rest at VI.

In the case of the direct cam-actuation of the pilot valves as shown byFigs. '7 and 8, the pick is timed in the usual manner by setting the camor cams earlier or later on the shaft.

In the case of the electro-magnetically actuated pilot valves as shownby Fig. 10, the timing of the pick is determined by the position of theslay cranks when the timing switch (2% or 2911) is closed by the cam.The timing may be adjusted by moving the cam 58 round the shaft 99 inthe usual manner, but the preferred method is by rocking the switch orswitches as a whole forward or backward around the aXis of the camshaft, which arrangement permits the timing of the pick to be adjustedwith great precision while the loom is running. Such rotary adjustmentof the timing switches is indicated by providing the casing in which theswitches are mounted with an arcuate slot 4! working over a fixed studprovided with a nut by which the casing can be locked in any desiredposition.

The power of the pick depends upon the volumetric capacity of thecharging bottle 5, and the predetermined pressure at which thecompressed air supply is maintained. With an air pressure of 60 lbs. p.s. i., the required capacity of the charging bottle is approximately 20cubic inches per one pound weight of shuttle and cop, so that for a fullshuttle weighing 5 lbs., the charging bottle should have a volumetriccapacity of about 100 cubic inches, which will provide a shuttledischarge velocity of approximately 45 feet per second.

The power of the pick is increased by an increase of the charging volumeof the bottle and also by increasing the maintained pressure of thecompressed air supply.

The air supply to each loom or each group of looms may be controlled byan adjustable reducing valve so as to maintain a suitable pressure,

and minor adjustments at individual looms then made by varying theeffective volume of each charging bottle. This may be constructed sothat it can be screwed in or out of the valve box 8 in order to vary theeffective volume of the bottle and, therefore, the volume of one chargeof compressed air. Alternatively, the bottle may be provided with apiston 3|, the position of which is readily adjustable by means of screw32 and hand wheel 33 as shown in Fig. 6.

With direct pneumatic picking of the shuttle, the shuttle boxes arenecessarily enclosed and consequently the weaver cannot withdraw ashuttle from a box by hand in the accustomed manner. In order to expelthe shuttle from the box but at low velocity, a hand operated valve 34is provided by which compressed air from the supply pipe A may beadmitted directly into the outer end of the shuttle box as shown in Fig.11. Such flow of air is preferably limited by a suitable restriction, orsuitably small pipe area, and the valve is of the self-closing type. InFig. 11, the valve 34 is temporarily opened by hand lever 35 connectedto the valve lever by link 36. When the handle is released, the valve isclosed by spring 31. These arrangements may be varied in detail.

Alternatively, such temporary flow of air into the shuttle box forgently expelling the shuttle may be controlled, as shown in Fig. 12, byan electro-magnetic valve 38 mounted on the slay and controlled by apush button 39 placed for convenient operation by the weaver, theenergising current for this purpose being drawn from battery 40 or othersource of electric power.

The pressure of air required for the slow expulsion of the shuttle fromthe shuttle box is very low and is normally not sufiicient to open thecheck valve 3 against the pressure of its closing spring 317.

I claim:

1. In a loom for weaving of the type referred to the combination withthe shuttle box and the shuttle of a charging bottle connected to asource of compressed air and to the shuttle box, a charging valvearranged between the bottle and the source of compressed air, and a pickvalve arranged between the bottle and the shuttle box, the chargingvalve and the pick valve being controlled from a rotating part of theloom so that they open and close in the desired sequence and thecharging valve being always closed when the pick valve is open.

2. In a loom for weaving of the type referred to the combination withthe shuttle box and the shuttle of a charging bottle connected to asource of compressed air and to the shuttle box, a charging valvearranged between the bottle and the source of compressed air, a pickvalve arranged between the bottle and the shuttle box, and a check valvewhich operates when a shuttle is entering the shuttle box to allow theescape of air therefrom at a rate which will have a cushioning effect tobring the shuttle to rest at the inner end of the shuttle and means toprevent the opening of the check valve when the pick valve is open, thecharging valve, the pick valve and the means preventing the opening ofthe pick valve so that the charging valve and the pick valve open in thedesired sequence, the charging valve being always closed and the checkvalve always held closed when the pick valve is open.

3. In a loom for weaving as in claim 2 the com; bination with thecharging valve, the pick valve and the means for preventing opening ofthe check valve of a pilot valve which controls a supply of compressedair to the aforesaid valves in the desired sequence.

4. In a loom for weaving as in claim 2 the combination with the chargingvalve, the pick valve and the means for preventing opening of the checkvalve of a pilot valve which controls a supply of compressed air to theaforesaid valves in the desired sequence and a cam rotating at half thespeed of the crank shaft of the loom actuating the said pilot valve.

5. In a loom for weaving as in claim 2 the com bination with thecharging valve, the pick valve and the check valve of a valve box, inwhich the three valves are located, arranged adjacent to the valve box,three relay pistons each operating in a relay cylinder in the valve andeach connected to one of the aforesaid valves, a pilot valve to controla supply of compressed air to said valves, a spring holding the chargingvalve on its seating but allowing it to be opened when compressed air issupplied to its relay cylinder by the pilot valve, a second springholding the pick valve on its seating but allowing it to be opened whencompressed air is supplied to its relay cylinder by the pilot valve anda third spring holding the check valve on its seating when thecompressed air is cut 0E from its relay cylinder, the said compressedair also holding the valve closed, the said third spring being of suchstrength that it will allow the escape of air from the shuttle box as ashuttle enters the latter at such a rate as will cushion the shuttle andbring it to rest at the inner end of the box.

6. In a loom for weaving as in claim 2 an auxiliary valve to supplycompressed air to the shuttle box to eject a shuttle therefrom at a slowspeed.

THOMAS HINDLE.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 445,395 Cranston et a1 Jan. 2'7,1891 2,454,603 Heaton Nov. 23, 1948

